Leptospirosis Vaccine May Be Killing Dogs

Leptospirosis is a treatable bacterial infection that can be contracted by dogs through contact with the urine of infected animals.

Vaccinations against leptospirosis are associated with severe adverse reactions in dogs and have been linked to 120 deaths over the last two years.

Although the infection is transmissible to humans, few cases are reported in the U.S.

Leptospirosis is a bacterial disease spread through the urine of infected rats, wildlife, and canines. Although it is treatable with antibiotics if it is caught early, the disease can be fatal to dogs—particularly puppies and young animals. Symptoms can range from mild lethargy and depression, to more serious symptoms like abdominal pain, jaundice, and liver damage. Leptospirosis illness leads to death in approximately 20 percent of cases, usually because the early symptoms are common to many diseases and may go unrecognized.

According to the American Veterinary Medical Association’s information of leptospirosis, symptoms may include “fever, shivering, muscle tenderness, reluctance to move, increased thirst, changes in the frequency or amount of urination, dehydration, vomiting, diarrhea, loss of appetite, lethargy, jaundice (yellowing of the skin and mucous membranes), or painful inflammation within the eyes,” among many others.1

Leptospirosis is not a new disease and actually is not a common problem in dogs (and does not appear to be a problem in cats), but increased awareness and testing have led to an increase in diagnosis.2

Risk and Prevention

Risk factors for contracting leptospirosis include drinking from contaminated sources, such as ponds, puddles or streams, roaming on rural properties where potentially infected wild animals may be, exposure to wild or farm animals, and contact with rats or infected dogs.1 Leptospirosis may also be contracted in urban areas through infected rodents. Preventive measures include reducing rodent populations, minimizing dogs’ exposure to wildlife, and avoiding stagnant-water conditions.

Potential Dangers of Leptospirosis Vaccines

There are vaccines against leptospirosis, but they are not on the “core schedule,” meaning they are only optionally offered. They also do not come highly recommended and many veterinarians are seriously opposed to them, maintaining among other things, that “the vaccine can actually cause the disease in dogs, and it has also been linked to early kidney failure in older animals.3

Vaccines against leptospirosis reportedly are associated with “as many or more adverse reactions than occur for any other” optional vaccine on the market.4 Others have agreed that the leptospirosis vaccines in general may “cause the most frequent and violent reactions” and, except in places where infection is a “severe threat, the benefits… do not outweigh the risks.”5

Nobivac L4, a new tetravalent vaccine against leptospirosis, was introduced in 2013 to cover newer strains of the bacteria found in Europe, and reports have since accumulated indicating that the vaccine has caused so many deaths and severe adverse reactions that the World Small Animal Veterinary Association (WSAVA) has warned against using it in puppies younger than 12 weeks of age, though other sources say the WSAVA disclaims that statement, and the vaccine is in fact routinely given to very young pups.6

According to the Daily Mail, more than 2,000 adverse reactions to the vaccine, including 120 deaths, have been linked to Nobivac L4 in the last two years.7 Reported side effects have included epileptic fits, swollen glands and blindness.

Dog breeder Carol Blackburn-Harvey recently brought attention to the issue in Great Britain when she lost her rare, prize dog to side effects of the vaccine. Manufactured by MSD Animal Health, a subsidiary of Merck Sharp & Dohme, Nobivac L4 is currently being monitored by the Government’s Veterinary Medicines Directorate (VMD), but its refusal to disclose the full number of known adverse reactions has sparked suspicions that the problem is being under-reported and the public under-informed.4

Bridgette Evans, another experienced and accredited dog breeder, who believes that every dog she has had vaccinated with Nobivac L4 was adversely affected, said:

Vets are not willing to admit or are in denial about the risk posed by the vaccine—it can kill perfectly fit and healthy dogs.4

A spokesperson for MSD, however, says:

The adverse event may have been related to an underlying disease, using other drugs at the same time, or other non-drug related causes. Therefore, marketing authorization holders and the authorities are obliged in the EU to apply a causality assessment to each case indicating the likelihood of an adverse event being linked to product administration.4

Leptospirosis in Humans

Though leptospirosis is a zoonotic infection, meaning it can be transmitted to humans, it is rarely seen in humans in the U.S. There are estimates of between 100 and 200 human cases per year and half of those cases occur in Hawaii.8 Infection is much more prevalent in tropical climates and in impoverished areas of the world with poor sanitation and underdeveloped infrastructures. Epidemics may occur when there are floods, and infections are more common in times of increased rainfall.

The World Health Organization (WHO) estimates the worldwide prevalence of leptospirosis in humans at 0.1 to 1 per 100,000 people in temperate climates and 10 or more per 100,000 in tropical climates. Occasional epidemics may increase the number to 100 or more per 100,000 people.9

36 Responses to "Leptospirosis Vaccine May Be Killing Dogs"

Elizabeth Young July 29, 2016 at 10:57 am

After the 1st year shots , most dogs will have immunity for at least 8 years , or , almost the length of life of the dog . Check out http://www.critterfixer.com , a Texas Vet’s website or Dr. Karen Becker’s website ( holistic vet ). Since I don’t over vaccinate my dogs have no weird skin allergies and no food allergies . I feed non-GMO dog food that is grain free . Major vaccine makers will not sponsor research on this because it may go against the bottom line . Same for traditional vets , who , like pediatricians , get office visit fees every time you bring your dog in for a battery of shots . Helps their bottom line . As for checking titers , a dog can have cellular immunity and no or low titers and still be immune to disease . Plus , they are expensive . Do ” the most nothing ” , feed the best food , exercise , don’t buy puppy mill dogs ( genetic problems ).

Repeating Dr Becker’s claim in your article is poor science…at best. I have NOT been a great proponent of Lepto protection for canines during my 45yrs of practice (even the newer lower antigen L4), but stating (without reference to the source) that science has demonstrated reversion to virulence for a killed bacterin and “the vaccine can actually cause the disease in dogs” undermines the believability of some other good points in your discussion about vaccine protocols.

I have also observed other “poor veterinary medical science” linked to the Mercola site in the past.

Lepto is no joke. I contracted it 19 years ago in Hawaii. People occasionally die from it there, if they leave it untreated. It is a spirochete, like Lyme disease, and I suspect it uses some of the same mechanisms to hide from the immune system within one’s cells by camouflage, moving into different life cycles when threatened, etc… How the hell some genius thinks they can vaccinate against something like that, I’d love to hear.

Me thinks you’ll be waiting a long time, unless you’re into reading a lot of baloney. But I doubt it.
I won’t consent to vaccinating my pets at all. The only 2 times my dog had to have a rabies vaccine was those times I (unfortunately) HAD to bring her to the vet for physical issues that I couldn’t address at home. Would that I could have!
Each time she had the rabies vaccine she was lethargic for several days.

I am sorry , Velobwoy, but your comment is pure nonsense. You think because an infection is severe the vaccine will be less effective? For your information, many “geniuses” have actually researched scientifically and proven that many vaccines safely prevent lethal diseases, as smallpox, meningitis, pneumonia, etc. This has also been shown clinically. I have not legitimately researched Leptospirosis vaccine for animals to evaluate it’s risks versus benefits so would not make such a ridiculous claim based on here-say and anecdotes. You could do this unless you rely on one of the radical anti vaccine sites that have no credibility.

The immunity that leptospirosis vaccinations give is short lasting perhaps a year, perhaps less in some dogs. Occasionally, the vaccine does not protect at all. Vaccine manufacturers have known the drawbacks of their leptospirosis vaccines for years. So you and your veterinarian must decide if your pet s risk of catching leptospirosis justifies yearly vaccination. In making that decision you must ask if your pet frequents areas that may harbor leptospirosis. You must also know if leptospirosis is occurring frequently in your community. You must also consider if your pet, or its siblings, have had previous vaccination reactions. Reactions also seem to occur more frequently in smaller breeds than larger ones.

My dog developed Pancreatitis 1 year ago after receiving the Lepto shot. Not realizing that this was the connection, she received another Lepto injection this year and 2 months later went into liver failure. I now see the correlation, and wish my Vet would have been honest and let me know that a 13 year old Pug did not need this. Thanks to the Vet being money hungry, instead of caring about my dog, she is no longer with us. Please do your research before allowing your vet to give your dog vaccines. 10-8-2016.

This one s for leptospirosis which is not recommended as a “core” vaccine to be given routinely to your dog unless in a leptospirosis area, though it has course of course become the norm for all dogs today.

Also i wanted to add that one of my dog got overvaccinated with rabbies vaccine because she was a rescue dog and she developped seizures and lost her hair all around her ears. After fighting quite a bit with the vet, i finally could obtain a written exemption of any further vaccinations . Why do vets wait for our pets to be in serious health geopardy to recognize that over vaccinations is so damaging to their health????

My Jack Russell, who is almost 15 and super healthy got her Lepto booster last week before we were leaving to move out west for the summer. We occasionally need to board our 2 dogs because of whitewater rafting trips, and they have to have a kennel cough vaccine and a lepto vaccine in order to board them. She started feeling poorly within a few days, and I could smell it on her breath that she was sick. She then developed a high fever and runny discharge from her nose accompanied by constant sneezing. She is very lethargic, but thankfully she is still eating and drinking well. My vet said that it probably wasn’t the vaccine, but I think it is. She’s never sick and this is very unlike her. They placed her on antibiotics and I’m hoping it’ll bring her around

Cathy, Did your dog get better? I have a Jack. He got a lepto shot today and seems to be experiencing similar symptoms. He can’t walk. I have to carry him around. Since it’s only been 5 hours, I’m just hoping it’ll get better.

Rebecca, my jack Russell is still ill. I have to carry her as well, but we discovered that she had a serious staph infection as well as e-coli. We got rid of the upper respiratory thing, and now it is returning. Meanwhile, $1500 later, I still believe with all of my heart it was the vaccine that started everything.

The UK version of L4 from Intervet/MSD Animal Health killed our 5 year old Akita. She stopped eating and lost 30% of her body weight over 6 weeks while thes struggled to find anything wrong. She fnally was put to sleep with nothing found to be wrong. The only trearment she had received at the vets was the injection of Nobivac L4 Leptospirosis vaccine.https://www.dropbox.com/s/zjn4dz7a7qgfw92/Nobivac%20L4%20Poster%20Ver2.jpg?dl=0

Ever since my pup had a reaction from the lepto. Vaccine he has become very aggressive in his behavior. He had a bad reaction from the vaccine and I had him treated but he now has become very aggressive. Could this be a result from the vaccine?

My 8 year old perfectly healthy xbreed lost her sight within 3 weeks of receiving her Lepto 4 booster. I was told she has a brain tumor but I now have serious doubts as she is still with us after nearly 9 months. I feel so helpless as there is nothing I can do to establish the truth and I have lost faith in vets as I feel these boosters are more about making money than caring for my dog. Think very seriously before consenting to your pet receiving this drug, I am convinced it is responsible for my dogs blindness and nobody will help !

My dog went into a chock 2 hours after the vaccination . He would stop for 15 minutes starring into a wall or a bush , without moving a muscle . Now , 4 months later , he is all of a sudden afraid of cars in the street . He eats and drinks as normally , but he is as far from
normal as can be .
He is a 9 years old Basset Fauve de Bretagne , the vet didn´t ask before she gave it to my dog and I had only asked for a Rabies vaccination .
None of the vets , I have taken my dog to , will accept any a these facts and treats me , like I am crazy . It is my 5.th dog , and I have had big dogs earlier , that went to training schools , one was even an Agilty champignon , so I am a very serious dog owner .

The Leptospirosis vaccine caused masticatory myositis in our son’s 8.5 year old Rottweiler almost 2 years ago. For anyone not aware of this terrible ailment, his jaw clamped totally shut, where it couldn’t not even be attempted to be open under heavy anesthesia. He could neither eat or drink. This ailment also went undiagnosed by the vet who administered the vaccine, and another vet that saw him. It was only after our own extensive reading, that did we on our own, that we figured out what was wrong with him, and then went to the vet with the recommendations based on our readings, for a course of action to save his life. It took almost a full year of prednisone for him to recover. Once he was off the prednisone, shortly after he developed Osteosarcoma in his front leg. He was sent to the Rainbow Bridge just last week. And he was a healthy dog prior to the vet convincing our son that this vaccine was required. He was never told that there were possible side effects, and why would he even think that there would be. After much reading, it is more than evident that he should never have been given that vaccination, nor should he have been given the rabies shot prior to a titre test. Although, he lived to be almost 11 years old, which is remarkable for a Rottweiler, he could of been spared a lot of pain and discomfort, had he not been given these unnecessary vaccines.

Pet Smart told me I needed to give this vaccine to my 7-year old malamute for her trip to Mexico. Absolutely a lie. She died three weeks later from the disease after terrible suffering. This vaccine should be banned. I was heart broken.

My 2 year old yellow lab did not have any reaction or issues after his first lepto shots as a puppy. He received the lepto shot in his upper left leg/hip area nearly 1 month ago and has had issues with intermittent pain in the left hip typically in the morning following vigorous exercise from the previous day. He went to the vet twice with negative exam and no diagnostic workup. They did not think it was the vaccine. His 3rd visit was to a different vet. hip xray was negative but pain was reproduced in the left hip on exam. he is on NSAIDs now for 7 days and rest for 2 weeks. Plan for ortho consult and further imaging if pain persists. I can not find any information on the web lepto shot and prolonged pain. I am wondering if anyone else has experienced this with their dog? The pain started the day after his vaccine. it seems to coincidental to not be related to the vaccine. Maybe improper vaccine injection and injury occurred?

I am so sorry to hear your baby is in pain. My 3mo pug Lilly received this bullsht vaccine on the 9th of April, and she has been in the hospital for 3 days now and is still not home. My little dumpling is way too small to have had this, and if she survives, she’s absolutely not having it again. I am also beating myself up because I blindly trusted the pet hospital to give her whatever they thought she needed, but now I know it’s all about money. The emergency room vet at a different hospital for critical care said to not let them inject her again. My Lilly immediately became lethargic, she lost her appetite, slept more than any baby should the rest of the day and night, she was shaking, coughing, vomiting and having diarrhea. She had just barely gotten over giardia. My baby also had severe pain like yours, it is one of the side effects (that they didn’t go over) and her little shoulder swelled up to the point that she barely wanted to move and had no interest in the food she usually destroys. I hope & pray our babies will pull through! This is heart wrenching

My beautiful 6 year old,8 lb. pom. Stella died 20 minutes after receiving this unnecessary vaccine. The allergic reaction was silent, terrifying and deadly. Do not let this happen to your pet. I raced her back to the vet and they couldn’t revive her and now I’m left with the “why” and I have no answers…I’m mad at my blind trust and don’t even want to face what I have to do today Say NO to this vaccine!!!

During a routine checkup for my 7yr old Pitbull, my vet said that he needed a Lepto vaccine shot. She never said a word about possible side affects. 2hrs after we got home he just seemed like he was in shock, or in a haze, he just stood staring at a wall. He wouldn’t sit down or lay down. Then he started panting rapidly and shaking as if he were freezing. After about 2hrs his shaking stopped but he still seemed like he didn’t know where he was at. My dog was in very good shape high energy before this shot, now he is very lethargic. I know for a fact this is a side affect from the Lepto vaccine. Its all about money people, Im very disappointed and very pissed off that someone I trusted would do this to my family member.

I have a female Jack Russell/ Ray Terrier who will turn 12 in June. When I first bought her in 2005, I took her for her checkup and vaccines. The vet gave her the Leptospirosis vaccine and on my drive home, my dog was yelping… screaming in intense pain, and the injection site was extremely swollen. I turned around and raced back as fast as I could to the vet and he gave her another vaccine for her reaction she experienced. He then told me that most dogs get a reaction from the shot. It isn’t really needed. It’s optional. I was so upset with myself that I didn’t even question the vaccine he suggested and that it was not needed, as well as it should never be given to a dog under a year. If I would have known then what I know now, I would’ve never said yes to that ridiculous vaccine. That vaccine should be banned. It’s cruel. I commend all the vets who refuse to give this vaccine. My heart goes out to all of you who have dogs that were hurt and are suffering from the effects of this vaccine. You are in my thoughts and I wish all the best of healing to you and your beautiful animals.

We have 4 dogs that went in for a rabies shot. Unfortunately without my permission the vet did what he wanted to all of them, including the lepto. My dog who will be 13, an Aussie/Husky mix got sick and had severe diarrhea. couldn’t walk or eat. I will never allow someone to do things without my permission and now I have vet bills to pay for after care.

I take my dogs to the dog park all the time so about a year ago I got the lepto vaccine after being told that they would catch it at the dog park. Two of my dogs are completely fine but my 3 year old Shepard/ dingo rescue developed focal seizures 1 month after having the vaccine and she would have 1 every month for 3 months. I took her to the vet and they put her on phenobarbital for seizures. She had her first gran male seizure today and I am convinced it was the lepto vaccine. She was perfectly healthy before the vaccine and now has seizures and she’s only 3! Poor pup. I’m sorry to everyone who has lost their fur babies to this awful vaccine. I only got the vaccine once and never went in for the follow up the next month as my sister who works for a rescue told me that she has seen a lot of bad effects from this vaccine.

My 12 year old healthy Jack Russell received her first Lepto in July at her yearly physical. With the second shot scheduled for 2 weeks later. We do live in an area where wildlife can get in our yard, so I thought I was doing the right thing. At that appt. I told them I was worried because her sight and hearing seemed to decline since the Lepto and I wasn’t sure she should receive the second one. They assured me it was fine. She just wasn’t the same after the second, little signs here and there. My sweet girl passed away in late August, healthy the month before. Think twice before agreeing to this vaccine. We are beyond devastated.

My 6 month hound rescue went to get checked. I trusted the vet would give him what he needed. Well he got a lepto vaccine. He is not the same dog. He had a reaction to this shot. Now he is on all kinds of meds . His liver has been affected. He is going for a ultraound tomorrow. My heart is hurting for him. Please please do research before letting them give your dog this vaccine. I’m hoping for the best.

We did the leptospirosis shot for both of our dogs, 12 & 6 1/2 back in May 2018. Our 6 1/2 year old was experiencing lameness & found out she had platelet issues. She’s been on prednisone for over 6 weeks. Every time we try to wean her off her platelets drop very low. The vet just told me to stop Lyme & leptospirosis vaccines for her in the future, we are stopping for both of our dogs and they recommend only do rabies. We love her dearly and have spent $800 or more for weekly jugular sticks to check her platelets. Never mind her voracious appetite and thirst. She’s like a crazy person. She keeps us up half the night and pees all over the house, I sometimes just cry because i feel so bad for her. We’re praying things get better for her.

Our dog Attitude had an absolutely perfect yearly exam. She was a senior, but was in literally perfect health. Her bloodwork was fantastic. At that exam, our vet pushed us to get the lepto vaccine because we are in the country and she might contract the disease unknowingly. One week after that perfect exam and that vaccine – she was gone. The vet insisted she had to have gotten into something, there was no way it was the vaccine. Not even possible. She was not one to “get into” things, and we keep everything potentially problematic put away and have baby locks on cabinet doors. I have a bunch of nosy cats – I have to do that. The vet said no way it could be the vaccine because the drug rep would have told them if there were potential side effects, especially to the degree of death. I was floored. That is by far the most naive thing I have ever heard from a vet. I even told her so. Do you think a drug rep is going to give you that information when they are there to make money, and to push you to get it for them. And that vet’s office is money hungry anyway, at least the owner is. I will now drive an hour to my current vet who is amazing. I have only gone back to that other vet to pick up a prescription called in from my new vet. And once when one of my cats got blocked and had to be seen immediately. Now, since I generally see another vet unless I have no choice, they won’t even fill prescriptions for me, per the owner’s orders. She is rude to me if she sees me there. I know I’m my heart that vaccine killed our girl. I will NEVER get it again. The only vaccines my animals get now is rabies. Period. And I only do that because it’s required by lanw.

Hi. I have two border collies. Neither of them were vaccinated for leptospirosis. We had a fenced in yard with a wire mesh to keep larger animals (like skunks, deer, raccoons) out…they never left that fenced area…but still small animals such as a mouse or squirrel could get in. My girl border collie who was very strong healthy and vibrant showed benign symptoms of lethargy and not wanting to eat (she can be finicky sometimes, so we weren’t extremely alarmed). We took her to the Dr the next day….and was diagnosed with hepatitis and treated for it and observed for 24 hours. Her kidneys started to fail next about 12 hours later….and then they did the SNAP test and it was negative. The MAT test they put in on Wednesday but they continued to treat her like she may have leptospirosis. She had multiple organ failure and we put her down on Friday. The MAT test came back in on Friday and confirmed acute leptospirosis. We have gone through our house and bleached everything, thrown out bedding, bleached areas in the large back yard where she could have contracted it. Do I get my other border collie this vaccine? I read all these entries and I don’t know what is worst…vaccinnated or unvaccinated? It was a horrible thing to watch my little girl die from leptospirosis.

I’ve been reading the sad stories of people who have lost their pets to this lepto vaccine. I am so sad that I allowed a vet at a mobile clinic to give this vaccine to my 14 year old Pomeranian. My fur baby went into stage 4 kidney failure and had elevated liver enzymes after being vaccinated–I took him to my vet and he said my dog probably already had a decline in kidney function, due to his age, before getting this vaccine. But this vaccine pushed him over the edge. He was eating, drinking and doing ok before getting it. But afterward, he had diarrhea, vomiting and he quit eating. I am now giving him subcutaneous IV fluids, anti-nausea medication and an appetite stimulant trying to get him back to where he was. I’m sad to say, it doesn’t look good. My vet said I need to start thinking about putting him down. I feel like our time was cut short by this vaccine. I’ve posted this article on my facebook page. I don’t want anyone to go through this with their furry family members. I am heartbroken and angry. I am sure the illness, leptospirosis is a dangerous disease. But, I should have taken my chances. My pomeranian was not a good candidate for this vaccine. I feel the vet should have known this. I just want others to make an informed decision. I had no idea. I wish I had researched this before allowing my pet to be vaccinated. Hindsight is 20/20.

My 6 month old lab had the Lepto vaccine and then experienced a grand mal seizure 6 days later. She couldn’t even walk, stand up or focus at 90 minutes after seizure. The vet brushed off my concerns about the timing of the vaccine and her seizure. I am absolutely convinced that this vaccine caused the seizure. I will never allow her to have it again. We are in the woods with her a lot, but have resigned ourselves to be aware if she should show any abnormal signs in the future that could indicate Lepto (or any other infection) and get her treatment as soon as possible. She has been seizure free foralmost a month–and even if she has them again in the future we will opt for homeopathic anti-seizure remedies instead of the harsh anti-seizure meds the vet suggests. Be careful, people. Fight for your fur babies. You have to be their advocates.